System for automatically measuring extension displacement of energy-releasing anchor rod based on magnetic mark positioning

Abstract

The invention discloses an energy-releasing anchor rod extension displacement automatic measurement system based on magnetic mark positioning, and relates to the technical field of tunnel engineering supporting. A separated magnetic mark array is integrated on a damping cylinder in the energy-releasing anchor rod extension displacement automatic measuring system, and a magnetic field induction sensing head is integrated on a damping block. The separated magnetic mark array comprises a plurality of separated magnetic mark units which are arranged at equal intervals in the axial direction of the damping cylinder; the magnetic field induction sensing head is used for sweeping the separated array along with the damping block and generating a characteristic electric signal for indicating the scanned magnetic marking unit by sensing a magnetic field peak value or a magnetic field characteristic change generated by the magnetic marking unit, so that the number of the scanned units is determined according to the characteristic electric signal; and the extension displacement of the energy-releasing anchor rod is calculated according to the number and the arrangement distance, so that the relative displacement of the damping block and the damping cylinder in the energy-releasing anchor rod covered by the sprayed concrete can be accurately and reliably measured, an observation channel does not need to be reserved, and the method has the characteristic of low cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of tunnel engineering support, and particularly relates to a release energy anchor rod elongation displacement automatic measurement system based on magnetic calibration positioning. BACKGROUND

[0002] Tunnel soft surrounding rock usually deforms greatly, and anchor rod is one of the necessary measures for tunnel soft surrounding rock support. Although ordinary rigid anchor rod can provide sufficient anchoring force, it has small elongation deformation and cannot adapt to the demand of large deformation of tunnel soft rock, so an elongation type constant resistance anchor rod (also called release energy anchor rod) appears. The release energy anchor rod can pull the damping block to extrude the damping pipe into the damping cylinder through the damping device composed of the damping block, the damping cylinder and the damping pipe when the anchor rod is subjected to tension (the tension comes from the force of the surrounding rock on the free side expanding outward due to the change of mechanical properties), so that the damping cylinder moves towards the damping block together with the damping pipe, and the damping pipe deforms in the direction away from the center of the anchor rod, thereby generating a certain resistance between the damping block and the damping pipe, and achieving the purpose of tunnel engineering support.

[0003] At present, the release energy anchor rod has been widely used in soft rock tunnel support, and the sliding displacement of the internal damping block relative to the damping cylinder is the effective elongation of the anchor rod (i.e. the elongation displacement of the release energy anchor rod). If the effective elongation can be accurately obtained, it will be of great significance for evaluating the support state and the stability of surrounding rock. However, after the installation of the release energy anchor rod, the damping device is often completely covered by sprayed concrete, making it very difficult to directly measure the internal relative displacement. In addition, the existing release energy anchor rod elongation displacement measurement technology generally has the following defects: complex structure and easy to damage, insufficient measurement accuracy, need to reserve an observation channel, and low reliability and high cost due to the integration of complex electronic and power systems in the anchor rod. SUMMARY

[0004] The purpose of the present application is to provide a release energy anchor rod elongation displacement automatic measurement system based on magnetic calibration positioning, so as to solve the problems of measurement difficulty, complex structure and easy to damage, insufficient measurement accuracy, need to reserve an observation channel, low reliability and high cost of the existing anchor rod elongation displacement measurement scheme.

[0005] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0006] The present application provides a release energy anchor rod elongation displacement automatic measurement system based on magnetic calibration positioning, which comprises an anchor rod and a damping device composed of a damping cylinder, a damping pipe and a damping block and arranged at the suspended section of the anchor rod. The damping cylinder is integrated with a detachable magnetic marker array, and the damping block is integrated with a magnetic field induction sensor head.

[0007] The split magnetic marker array includes multiple split magnetic marker units that are equally spaced along the axial direction of the damping cylinder on the damping cylinder.

[0008] The magnetic field sensing head is used to scan the split magnetic marker array together with the damping block as the damping cylinder and the damping tube move toward the damping block. It generates a characteristic electrical signal to indicate that the split magnetic marker units have been scanned by sensing the magnetic field peak or magnetic field characteristic changes generated by the split magnetic marker units. The number of split magnetic marker units that have been scanned is determined based on the characteristic electrical signal. Then, the energy release anchor bolt elongation displacement is calculated based on the number and the arrangement spacing of the split magnetic marker array.

[0009] Based on the above-mentioned invention, a new, simple, inexpensive, and reliable automatic measurement scheme for the elongation displacement of energy-releasing anchor bolts is provided. Specifically, a separate magnetic marker array is integrated on the damping cylinder, and a magnetic field induction sensor head is integrated on the damping block. The separate magnetic marker array includes multiple separate magnetic marker units arranged at equal intervals along the axial direction of the damping cylinder. The magnetic field induction sensor head is used to scan the separate array along with the damping block, and generates a characteristic electrical signal indicating that the magnetic marker units have been scanned by sensing the peak or characteristic changes in the magnetic field generated by the magnetic marker units. The number of units scanned is determined based on the characteristic electrical signal, and the elongation displacement of the energy-releasing anchor bolt is calculated based on the number and spacing. Thus, even with a simple, passive, or basic sensing structure, the relative displacement between the damping block and the damping cylinder inside the energy-releasing anchor bolt covered by shotcrete can be accurately and reliably measured. Furthermore, no observation channel needs to be reserved, and the system is inexpensive, making it easy to apply and promote in practice.

[0010] In one possible design, a connector and an external measuring instrument are also included, wherein the connector is electrically connected to the magnetic field sensing head via a wire, and the external measuring instrument includes an interface unit, a signal detection and processing unit, and a displacement calculation unit that are electrically connected in sequence.

[0011] The interface unit is used to mate with the connector;

[0012] The signal detection and processing unit is used to receive the characteristic electrical signal from the magnetic field sensing head when the interface unit is docked with the connector, and to determine the number of the separated magnetic marker units that have been scanned based on the characteristic electrical signal.

[0013] The displacement calculation unit is used to calculate the elongation displacement of the energy-releasing anchor rod based on the quantity and the arrangement spacing of the split magnetic marker array.

[0014] In one possible design, the signal detection and processing unit includes a signal amplification circuit, a filtering circuit, a shaping circuit, and a counter for pulse counting or a microprocessor for signal pattern recognition.

[0015] In one possible design, the external measuring instrument further includes an excitation unit electrically connected to the interface unit and / or a display unit electrically connected to the displacement calculation unit, wherein the excitation unit is used to power the magnetic field sensing head when the interface unit is docked with the connector, and the display unit is used to output and display the elongation displacement of the energy-releasing anchor rod.

[0016] In one possible design, the external measuring instrument also includes an automated monitoring interface unit that is electrically connected to the interface unit, the signal detection and processing unit, or the displacement calculation unit;

[0017] The automated monitoring interface unit is used to convert the characteristic electrical signal from the magnetic field sensing head into a data stream in real time when electrically connected to the interface unit, so as to transmit the data stream to the remote end in real time; or to convert the quantity into a first signal to be transmitted when electrically connected to the signal detection and processing unit, so as to transmit the first signal to be transmitted to the remote end in real time, offline, at a set time, or when a preset trigger condition is met; or to convert the energy release anchor bolt elongation displacement into a second signal to be transmitted when electrically connected to the displacement calculation unit, so as to transmit the second signal to be transmitted to the remote end in real time, offline, at a set time, or when a preset trigger condition is met.

[0018] In one possible design, a cloud monitoring platform with a communication connection to the automated monitoring interface unit is also included;

[0019] The cloud monitoring platform is used to acquire the elongation displacement of the energy-releasing anchor bolt based on data from the automated monitoring interface unit, record the time series of the elongation displacement of the energy-releasing anchor bolt, determine the current displacement rate in real time based on the time series, and finally, if the current displacement rate is found to exceed a preset rate threshold, trigger the execution of an abnormal anchor bolt elongation displacement alarm action.

[0020] In one possible design, the cloud monitoring platform is also used to perform multi-anchor network monitoring when monitoring the elongation displacement of the released anchor bolts, as follows: the monitoring data of multiple anchor bolts are distinguished by a unique identifier, and the overall state of the support area is evaluated based on the monitoring data to obtain a multi-anchor bolt displacement heat map of the support area, wherein the support area is provided with the multiple anchor bolts.

[0021] In one possible design, when the damping cylinder is made of a non-ferromagnetic material, the separate magnetic marking unit is made of a magnet.

[0022] Alternatively, when the damping cylinder is made of a low-permeability material, the split magnetic marking unit is made of a strong magnetic steel or permanent magnet material.

[0023] In one possible design, two adjacent separate magnetic tag units in the separate magnetic tag array have the same magnetic pole orientation;

[0024] Alternatively, all the separate magnetic marker units in the separate magnetic marker array have staggered magnetic pole orientations along the axial direction of the damping cylinder;

[0025] Alternatively, each of the separate magnetic marker units in the separate magnetic marker array has an independently encoded magnetic pole orientation.

[0026] In one possible design, the spacing between the discrete magnetic marker arrays is greater than or equal to 0.5 cm and less than or equal to 1.5 cm.

[0027] And / or, the magnetic field sensing head adopts a digital switch type Hall sensor or a linear Hall sensor.

[0028] The beneficial effects of the above scheme are:

[0029] (1) This invention provides a simple, easy-to-implement, inexpensive and reliable new solution for automatic measurement of the elongation displacement of an energy-releasing anchor rod. Specifically, a separate magnetic marker array is integrated on the damping cylinder, and a magnetic field induction sensor head is integrated on the damping block. The separate magnetic marker array includes multiple separate magnetic marker units arranged at equal intervals along the axial direction of the damping cylinder. The magnetic field induction sensor head is used to scan the separate array together with the damping block, and generates a characteristic electrical signal to indicate that the magnetic marker units have been scanned by sensing the magnetic field peak or magnetic field characteristic changes generated by the magnetic marker units. The number of units that have been scanned can be determined based on the characteristic electrical signal, and the elongation displacement of the energy-releasing anchor rod can be calculated based on the number and the arrangement spacing. In this way, even when the internal sensing structure of the system is simple, passive or contains only basic sensing elements, the relative displacement between the damping block and the damping cylinder inside the energy-releasing anchor rod covered by shotcrete can be measured accurately and reliably. Furthermore, no observation channel needs to be reserved, and it has the characteristics of low cost.

[0030] (2) The internal structure is extremely simple and reliable: the anchor bolt only needs to be fixedly arranged with passive magnetic markers and basic Hall sensors and leads, without complex electronic components and power supply, which greatly improves the long-term reliability under harsh working conditions.

[0031] (3) External measurements can be performed as needed: the measurement is powered and processed by an external instrument only, without having to consider the internal battery life and static power consumption.

[0032] (4) The measurement principle is clear and not easy to drift: Based on counting or pattern recognition, it is relatively less affected by long-term sensor drift or uniform background magnetic field interference (compared to the scheme that relies on the accurate value of analog quantity);

[0033] (5) High precision is easy to achieve: the displacement resolution depends directly on the spacing of the magnetic markers, and the precision can be improved by reducing the spacing (the sensor resolution needs to be taken into account);

[0034] (6) High cost-effectiveness: The cost of the anchor bolt itself is relatively low, and the main cost lies in the reusable external measuring instruments;

[0035] (7) Seamless integration with automated monitoring: Through standardized electrical signal interfaces (digital / analog) and communication protocols, this system can be directly connected to existing industrial IoT platforms without customized development, significantly reducing integration costs and supporting long-term continuous monitoring data accumulation. It provides high spatiotemporal resolution data support for surrounding rock stability analysis and support effectiveness assessment, breaking through the sampling frequency limitations of traditional manual inspections, and facilitating practical application and promotion. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Fig. 1 This is a schematic diagram of the automatic measurement system for the elongation displacement of an energy-releasing anchor bolt based on magnetic marker positioning, provided in an embodiment of the present invention.

[0038] Fig. 2 An example diagram of the internal structure of an external measuring instrument provided in an embodiment of the present invention. Detailed Implementation

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in conjunction with the accompanying drawings and descriptions of the embodiments or the prior art. Obviously, the following description of the structure of the accompanying drawings is only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these embodiments without creative effort. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0040] It should be understood that although the terms "first" and "second", etc., may be used herein to describe various objects, these objects should not be limited by these terms. These terms are only used to distinguish one object from another. For example, the first object may be referred to as the second object, and similarly, the second object may be referred to as the first object, without departing from the scope of the exemplary embodiments of the invention.

[0041] It should be understood that the term "and / or" that may appear in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, or A and B exist simultaneously. Another example is A, B and / or C, which can mean that any one of A, B, and C or any combination thereof exists. The term " / and" that may appear in this document describes another relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone or A and B exist simultaneously. In addition, the character " / " that may appear in this document generally indicates that the related objects before and after it are in an "or" relationship.

[0042] Example

[0043] like Figs. 1-2 As shown, the automatic measurement system for the elongation displacement of the energy-releasing anchor bolt provided in this embodiment, based on magnetic marker positioning, includes, but is not limited to, an anchor bolt 1 and a damping device consisting of a damping cylinder 2, a damping tube 3, and a damping block 4, arranged in the suspended section of the anchor bolt 1. The damping cylinder 2 integrates a separate magnetic marker array, and the damping block 4 integrates a magnetic field sensing head 6. The aforementioned anchor bolt 1, damping cylinder 2, damping tube 3, and damping block 4 are all conventional configurations of existing energy-releasing anchor bolts, and their structural relationships will not be elaborated here.

[0044] The separate magnetic marker array includes, but is not limited to, multiple separate magnetic marker units 5 arranged at equal intervals along the axial direction of the damping cylinder 2 on the damping cylinder 2. For example... Fig. 1As shown, by arranging the multiple separate magnetic marker units 5 at equal intervals, a magnetic scale can be formed on the damping cylinder 2 (each separate magnetic marker unit 5 corresponds to a scale line on the magnetic scale, and the existence of the corresponding scale line can be sensed through the magnetic field measurement results of the corresponding unit). To ensure low interference of the damping cylinder 2 to the magnetic field measurement, preferably, when the damping cylinder 2 is made of a non-ferromagnetic material, the separate magnetic marker units 5 are made of magnets; or, when the damping cylinder 2 is made of a low permeability material (e.g., aluminum alloy or austenitic stainless steel), the separate magnetic marker units 5 are made of strong magnetic magnets (e.g., magnets made of ferromagnetic or ferrimagnetic materials) or permanent magnets. The shape of the separate magnetic marker units 5 can be block-shaped (e.g., small permanent magnet blocks) or sheet-shaped (e.g., magnetic steel sheets). Specifically, adjacent two separate magnetic marker units 5 in the separate magnetic marker array may have the same magnetic pole orientation. Alternatively, to generate more easily detectable magnetic field changes, all separate magnetic marker units 5 in the separate magnetic marker array preferably have staggered magnetic pole orientations along the axial direction of the damping cylinder 2. Or, to achieve more complex functions (such as partial absolute positioning capability or direction determination), each separate magnetic marker unit 5 in the separate magnetic marker array preferably has an independently coded magnetic pole orientation, so as to identify different separate magnetic marker units 5 through different magnetic field changes, and then realize the aforementioned more complex functions based on the known positions of the separate magnetic marker units 5. In addition, the arrangement spacing of the separate magnetic marker array is used to determine the spatial resolution of the system, that is, the displacement measurement accuracy of this measurement system, which can be greater than or equal to 0.5 cm and less than or equal to 1.5 cm, for example, 1 cm.

[0045] The magnetic field sensing head 6 is used to scan the separate magnetic marker array along with the damping block 4 as the damping cylinder 2 and the damping tube 3 move toward the damping block 4. It generates a characteristic electrical signal indicating that the separate magnetic marker units 5 have been scanned by sensing the magnetic field peaks or changes in magnetic field characteristics generated by the separate magnetic marker units 5. Based on this characteristic electrical signal, the number of separate magnetic marker units 5 that have been scanned is determined, and then the elongation displacement of the energy-releasing anchor is calculated based on the number and the spacing of the separate magnetic marker array. Since the magnetic field sensing head 6 enters the damping cylinder 2 along with the damping block 4, it also scans the separate magnetic marker array at close range along with the damping block 4. During the scanning process, it generates a characteristic electrical signal indicating that the separate magnetic marker units 5 have been scanned by sensing the magnetic field peaks or changes in magnetic field characteristics generated by the separate magnetic marker units 5. Specifically, the magnetic field sensing head 6 can be, but is not limited to, a digital switch-type Hall sensor or a linear Hall sensor. When the digital switch-type Hall sensor is used, the characteristic electrical signal is a pulse signal with high and low level characteristics. Each pulse represents the passage of one of the separated magnetic marker units 5. Therefore, the number of separated magnetic marker units 5 that have been passed can be determined by counting the pulses based on the characteristic electrical signal. When the linear Hall sensor is used, the characteristic electrical signal is an analog voltage signal. Peaks (equivalent to pulses representing the passage of one separated magnetic marker unit 5) can be identified by peak detection or threshold comparison of the analog voltage signal. Therefore, the number of separated magnetic marker units 5 that have been passed can also be determined by counting the peaks based on the characteristic electrical signal. Furthermore, the number of magnetic field sensing heads 6 can be one, two, or more, and they can be integrated onto the damping block 4 using conventional fixing methods.

[0046] Specifically, based on the quantity and the spacing of the separate magnetic marker array, the elongation displacement of the energy-releasing anchor is calculated, including but not limited to: neglecting the initial distance between the magnetic field sensing head 6 and the first separate magnetic marker unit 5 in the separate magnetic marker array facing the damping cylinder 2, the elongation displacement ΔL of the energy-releasing anchor is calculated as ΔL = N × d, where N represents the quantity and d represents the spacing. Furthermore, in the mode of continuous measurement using the linear Hall sensor, the elongation displacement ΔL of the energy-releasing anchor can also be calculated based on the characteristic electrical signal, which is an analog voltage signal, according to the following formula: ΔL = (V out -V0)÷S, where V0 represents the initial bias voltage, V outThe output voltage of the linear Hall sensor is represented by S, which represents the pre-calibrated sensitivity coefficient (which determines the system resolution); and when two linear Hall sensors in an orthogonal arrangement are used for continuous measurement, the phase difference φ = arctan(V) can also be used as the basis for the measurement. H1 ÷V H2 The direction of displacement is determined by the sign of φ (positive indicates anchor bolt extension, negative indicates anchor bolt contraction), where V H1 V represents the output voltage of one of the linear Hall sensors. H2 This represents the output voltage of another linear Hall sensor.

[0047] Based on the detailed structural description of the aforementioned system, a novel, simple, inexpensive, and reliable automatic measurement scheme for the elongation displacement of energy-releasing anchor bolts is provided. This scheme integrates a separate magnetic marker array on the damping cylinder and a magnetic field induction sensor head on the damping block. The separate magnetic marker array includes multiple separate magnetic marker units arranged at equal intervals along the axial direction of the damping cylinder. The magnetic field induction sensor head scans the separate array along with the damping block and generates a characteristic electrical signal indicating the magnetic marker units that have been scanned by sensing the magnetic field peak or characteristic changes generated by the magnetic marker units. The number of units scanned is determined based on the characteristic electrical signal, and the elongation displacement of the energy-releasing anchor bolt is calculated based on the number and spacing. Thus, even with a simple, passive, or basic sensing structure, the relative displacement between the damping block and the damping cylinder inside the energy-releasing anchor bolt covered by shotcrete can be accurately and reliably measured. Furthermore, it eliminates the need for a pre-reserved observation channel and is cost-effective, facilitating practical application and widespread adoption.

[0048] Preferably, it also includes a connector 7 and an external measuring instrument, wherein the connector 7 is electrically connected to the magnetic field sensing head 6 via wires 70, and the external measuring instrument includes, but is not limited to, an interface unit, a signal detection and processing unit, and a displacement calculation unit connected in sequence; the interface unit is used to mate with the connector 7; the signal detection and processing unit is used to receive the characteristic electrical signal from the magnetic field sensing head 6 when the interface unit mates with the connector 7, and to determine the number of the separated magnetic marker units 5 that have been scanned based on the characteristic electrical signal; the displacement calculation unit is used to calculate the elongation displacement of the energy release anchor rod based on the number and the arrangement spacing of the separated magnetic marker array. The number of wires 70 is at least two (preferably three or more) to power the magnetic field sensing head 6 and output the characteristic electrical signal; preferably, as Fig. 2As shown, the external measuring instrument also includes an excitation unit electrically connected to the interface unit; the excitation unit is used to power the magnetic field sensing head 6 when the interface unit is connected to the connector 7; the excitation unit is electrically connected to the internal power supply of the external measuring instrument, which integrates a battery and power management module, and is also used to power other units within the external measuring instrument. The specific working principle of the signal detection and processing unit will not be elaborated here. In order to better complete signal detection and processing, preferably, the signal detection and processing unit includes, but is not limited to, a signal amplification circuit, a filtering circuit, a shaping circuit, and a counter for pulse counting or a microprocessor for signal pattern recognition, etc., wherein the signal amplification circuit, the filtering circuit, and the shaping circuit are used to amplify, filter, and shape the characteristic electrical signal respectively, and can be implemented using existing corresponding functional circuits; the signal pattern recognition can refer to, but is not limited to, identifying whether the characteristic electrical signal is a pulse signal or an analog voltage signal, so as to perform pulse counting, displacement calculation, or even movement direction determination, etc.; the hardware structure of the counter and the microprocessor can be implemented using existing device chips and their peripheral circuits. To enable on-site demonstration of the elongation displacement of the released anchor bolt, preferably, the external measuring instrument further includes a display unit electrically connected to the displacement calculation unit, wherein the display unit is used to output and display the elongation displacement of the released anchor bolt. Furthermore, the external measuring instrument may also include, but is not limited to, a storage unit and a button unit electrically connected to the displacement calculation unit, wherein the storage unit is used, but is not limited to, to store calibration data such as the arrangement spacing d or the sensitivity coefficient S, and the elongation displacement of the released anchor bolt, and the button unit is used to input the user's on-site operation signals; the external measuring instrument adopts a handheld instrument structure for on-site handheld operation.

[0049] Further preferably, the external measuring instrument also includes an automated monitoring interface unit electrically connected to the interface unit, the signal detection and processing unit, or the displacement calculation unit. The automated monitoring interface unit, when electrically connected to the interface unit, converts the characteristic electrical signal from the magnetic field sensing head 6 into a data stream in real time, so as to transmit the data stream to a remote end in real time; or, when electrically connected to the signal detection and processing unit, converts the quantity into a first signal to be transmitted, so as to transmit the first signal to be transmitted in real time, offline, at a set time, or when a preset trigger condition (e.g., the quantity reaches a preset quantity threshold) is met; or, when electrically connected to the displacement calculation unit, converts the energy release anchor bolt elongation displacement into a second signal to be transmitted, so as to transmit the second signal to be transmitted in real time, offline, at a set time, or when a preset trigger condition (e.g., the elongation displacement reaches a preset displacement threshold) is met, so as to transmit the second signal to a remote end. The data stream needs to be recognizable by the remote automated platform, and the specific conversion process is based on existing technology, so as to achieve seamless integration with the remote monitoring platform and support long-term continuous monitoring and remote transmission. Specifically, the first signal to be transmitted may be, but is not limited to, a standardized signal in the following form: a pulse signal, that is, the quantity is encoded into a standard digital signal (e.g., a TTL level signal or a signal suitable for standard industrial communication protocols such as RS485 / CAN bus protocol). This signal is particularly suitable for the case where the magnetic field sensing head 6 uses the digital switch type Hall sensor. The second signal to be transmitted may be, but is not limited to, a standardized signal in the following form: an analog voltage signal, that is, the energy release anchor rod elongation displacement is converted into an analog voltage signal (e.g., 0-5V or 4-20mA current loop) to adapt to the analog input interface of the industrial control system. This signal is particularly suitable for the case where the magnetic field sensing head 6 uses the linear Hall sensor. Furthermore, the automated monitoring interface unit can transmit the data stream, the first signal to be transmitted, or the second signal to be transmitted via wired communication (e.g., integrating RS485, Ethernet, or industrial bus interfaces and connecting to a local data acquisition unit or gateway via cable), or it can transmit the data stream, the first signal to be transmitted, or the second signal to be transmitted via wireless communication (e.g., integrating LoRa, NB-IoT, or 4G modules and supporting access from remote terminals such as personal computers or smartphones).

[0050] Further preferably, the system also includes a cloud monitoring platform with a communication connection to the automated monitoring interface unit. The cloud monitoring platform is used to acquire the elongation displacement of the released anchor bolt based on data from the automated monitoring interface unit, record the time series of the elongation displacement, determine the current displacement rate in real time based on the time series, and finally trigger an abnormal anchor bolt elongation displacement alarm action if the current displacement rate exceeds a preset rate threshold. The cloud monitoring platform is also used to perform multi-anchor bolt network monitoring in the following manner when monitoring the elongation displacement of the released anchor bolt: it distinguishes the monitoring data of multiple anchor bolts using a unique identifier (such as an anchor bolt ID), and performs an overall status assessment of the support area based on the monitoring data to obtain a multi-anchor bolt displacement heat map of the support area, wherein the support area contains the multiple anchor bolts. Furthermore, the cloud monitoring platform can also be remotely controlled and triggered in the following manner: it supports the platform issuing commands to activate the data acquisition function of the external measuring instrument according to a preset cycle (such as once per hour) or event triggering (such as a sudden displacement change).

[0051] In summary, the automatic measurement system for the elongation displacement of the energy-releasing anchor bolt provided in this embodiment has the following technical advantages:

[0052] (1) This embodiment provides a new solution for automatic measurement of the elongation displacement of the energy release anchor rod, which is simple, easy to implement and inexpensive and reliable. The damping cylinder is integrated with a separate magnetic marker array, and the damping block is integrated with a magnetic field induction sensor head. The separate magnetic marker array includes multiple separate magnetic marker units arranged at equal intervals along the axial direction of the damping cylinder. The magnetic field induction sensor head is used to scan the separate array together with the damping block, and generates a characteristic electrical signal to indicate that the magnetic marker units have been scanned by sensing the magnetic field peak or magnetic field characteristic change generated by the magnetic marker units. The number of units that have been scanned is determined according to the characteristic electrical signal, and the elongation displacement of the energy release anchor rod is calculated according to the number and the arrangement spacing. In this way, even when the internal sensing structure of the system is simple, passive or only contains basic sensing elements, the relative displacement between the damping block and the damping cylinder inside the energy release anchor rod covered by sprayed grout can be measured accurately and reliably. There is no need to reserve an observation channel, and it has the characteristics of low cost.

[0053] (2) The internal structure is extremely simple and reliable: the anchor bolt only needs to be fixedly arranged with passive magnetic markers and basic Hall sensors and leads, without complex electronic components and power supply, which greatly improves the long-term reliability under harsh working conditions.

[0054] (3) External measurements can be performed as needed: the measurement is powered and processed by an external instrument only, without having to consider the internal battery life and static power consumption.

[0055] (4) The measurement principle is clear and not easy to drift: Based on counting or pattern recognition, it is relatively less affected by long-term sensor drift or uniform background magnetic field interference (compared to the scheme that relies on the accurate value of analog quantity);

[0056] (5) High precision is easy to achieve: the displacement resolution depends directly on the spacing of the magnetic markers, and the precision can be improved by reducing the spacing (the sensor resolution needs to be taken into account);

[0057] (6) High cost-effectiveness: The cost of the anchor bolt itself is relatively low, and the main cost lies in the reusable external measuring instruments;

[0058] (7) Seamless integration with automated monitoring: Through standardized electrical signal interfaces (digital / analog) and communication protocols, this system can be directly connected to existing industrial IoT platforms without customized development, significantly reducing integration costs and supporting long-term continuous monitoring data accumulation. It provides high spatiotemporal resolution data support for surrounding rock stability analysis and support effectiveness assessment, breaking through the sampling frequency limitations of traditional manual inspections, and facilitating practical application and promotion.

[0059] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An automatic measurement system for the elongation displacement of an energy-releasing anchor rod based on magnetic marker positioning, comprising an anchor rod (1) and a damping device consisting of a damping cylinder (2), a damping tube (3), and a damping block (4) arranged in the suspended section of the anchor rod (1), characterized in that, The damping cylinder (2) is integrated with a separate magnetic marker array, and the damping block (4) is integrated with a magnetic field sensing head (6); The split magnetic marker array includes multiple split magnetic marker units (5) arranged at equal intervals along the axial direction of the damping cylinder (2) on the damping cylinder (2); The magnetic field sensing head (6) is used to scan the split magnetic marker array together with the damping block (4) as the damping cylinder (2) and the damping tube (3) move toward the damping block (4), and generate a characteristic electrical signal to indicate that the split magnetic marker unit (5) has been scanned by sensing the magnetic field peak or magnetic field characteristic change generated by the split magnetic marker unit (5), so as to determine the number of the split magnetic marker units (5) that have been scanned according to the characteristic electrical signal, and then calculate the energy release anchor rod elongation displacement according to the number and the arrangement spacing of the split magnetic marker array.

2. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 1, characterized in that, It also includes a connector (7) and an external measuring instrument, wherein the connector (7) is electrically connected to the magnetic field sensing head (6) via a wire (70), and the external measuring instrument includes an interface unit, a signal detection and processing unit and a displacement calculation unit that are electrically connected in sequence; The interface unit is used to dock with the connector (7); The signal detection and processing unit is used to receive the characteristic electrical signal from the magnetic field sensing head (6) when the interface unit docks with the connector (7), and to determine the number of the separated magnetic marker units (5) that have been scanned based on the characteristic electrical signal. The displacement calculation unit is used to calculate the elongation displacement of the energy-releasing anchor rod based on the quantity and the arrangement spacing of the split magnetic marker array.

3. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 2, characterized in that, The signal detection and processing unit includes a signal amplification circuit, a filtering circuit, a shaping circuit, and a counter for pulse counting or a microprocessor for signal pattern recognition.

4. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 2, characterized in that, The external measuring instrument also includes an excitation unit electrically connected to the interface unit and / or a display unit electrically connected to the displacement calculation unit, wherein the excitation unit is used to power the magnetic field sensing head (6) when the interface unit is connected to the connector (7), and the display unit is used to output and display the elongation displacement of the energy release anchor rod.

5. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 2, characterized in that, The external measuring instrument also includes an automated monitoring interface unit that is electrically connected to the interface unit, the signal detection and processing unit, or the displacement calculation unit; The automated monitoring interface unit is used to convert the characteristic electrical signal from the magnetic field sensing head (6) into a data stream in real time when electrically connected to the interface unit, so as to transmit the data stream to the remote end in real time; or to convert the quantity into a first signal to be transmitted when electrically connected to the signal detection and processing unit, so as to transmit the first signal to be transmitted to the remote end in real time, offline, at a set time, or when a preset trigger condition is met; or to convert the energy release anchor rod elongation displacement into a second signal to be transmitted when electrically connected to the displacement calculation unit, so as to transmit the second signal to be transmitted to the remote end in real time, offline, at a set time, or when a preset trigger condition is met.

6. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 5, characterized in that, It also includes a cloud monitoring platform with a communication connection to the automated monitoring interface unit; The cloud monitoring platform is used to acquire the elongation displacement of the energy-releasing anchor bolt based on data from the automated monitoring interface unit, record the time series of the elongation displacement of the energy-releasing anchor bolt, determine the current displacement rate in real time based on the time series, and finally, if the current displacement rate is found to exceed a preset rate threshold, trigger the execution of an abnormal anchor bolt elongation displacement alarm action.

7. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 6, characterized in that, The cloud monitoring platform is also used to perform multi-anchor network monitoring in the following manner when monitoring the elongation displacement of the energy-releasing anchor bolts: the monitoring data of multiple anchor bolts are distinguished by a unique identifier, and the overall status assessment of the support area is performed based on the monitoring data to obtain a multi-anchor bolt displacement heat map of the support area, wherein the support area is provided with the multiple anchor bolts.

8. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 1, characterized in that, When the damping cylinder (2) is made of a non-ferromagnetic material, the split magnetic marking unit (5) is made of a magnet. Alternatively, when the damping cylinder (2) is made of a low permeability material, the split magnetic marking unit (5) is made of a strong magnetic steel or permanent magnet material.

9. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 1, characterized in that, Two adjacent separate magnetic tag units (5) in the separate magnetic tag array have the same magnetic pole orientation; Alternatively, all the separate magnetic marker units (5) in the separate magnetic marker array have staggered magnetic pole orientations along the axial direction of the damping cylinder (2); Alternatively, each of the separate magnetic tag units (5) in the separate magnetic tag array has an independently encoded magnetic pole orientation.

10. The automatic measurement system for the elongation displacement of the energy-releasing anchor bolt as described in claim 1, characterized in that, The spacing between the array of separate magnetic markers is greater than or equal to 0.5 cm and less than or equal to 1.5 cm. And / or, the magnetic field sensing head (6) adopts a digital switch type Hall sensor or a linear Hall sensor.

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